Patent GB-278755-A (GB)
Title: Improvements in and connected with talking machines
IPC: G11B17/00
Filed: 1927-10-10
Abstract: 278,755. Mitchell, F.G. Oct. 8, 1926., [Convention date]. Driving; speed-regulating; cases.-Consists mainly in improvements in means for winding and regulating the speed of the spring motor of a gramophone. In the machine shown, the motor comprises two drums 4, 5, geared together by wheels 6, 7. Springs within the drums are connected to the drums and to spindles 4<1>, 8<1> respectively, the spindle 8<1> bearing a wheel 8 by which the drive is transmitted to the turntable spindle 13 through glaring 9, 11, 12. On the spindle 4<1> are mounted ratchet pinions 37, 38, gearing respectively with oppositely-disposed sectors 35, 36 carried by a lever 34 which is pivoted on the spindle 13. When this lever is reciprocated, the spring in the drum 4 is wound up. each strobe of the lever, in either direction, causing a partial rotation of the winding-spindle 4<1> by of one or the other of the ratchet pinions. When the spring in the drum 4 has been wound, the casing rotates and effects the winding-up of the spring in the drum 5. A centrifugal governor 22, 23, 24 is driven in the usual way by worm-gearing from the turntable spindle 13. The friction-pad 24 of the governor is adjustable relatively to the rotary disc 23, which moves along the axis of the governor, by means of a worm-wheel 27 on a screwed rod 25, a worm engaging with the wheel 27 being carried by a hand-operated rod 29. The motor may have more than two spring drums, connected by gearing so that they can be wound up successively by the means described. The framework of the motor is placed in a circular casing 30, having a detachable top 31, which is formed with a curved rim 32 through which project the various control rods and levers such as 29. Knobs on the ends of these levers lie in the recess formed by the rim. A removable cover 33 fits on the casing, and within it records may be stored and held by means of a nut fitted on to a central threaded stem 59, the nut resting on the end of turntable spindle. The Specification, as open to inspection under Sect. 91 (3) (a), comprises also the following subject-matter, which does not appear in the Specification as accepted. Speed-regulating.-Means may be provided to vary the angular speed of the turntable automaticallv whereby a constant linear speed of the record track in engagement with the needle is produced- In this case, the pad 24 may be dispensed with, another pad 74, operated by the mechanism shown in Fig. 11, (Cancelled) being provided. In this construction, the pad 74 which coacts with the rotary disc 23 of the governor, is fixed on a screwed rod 73, which is longitudinally movable by means of a nut 71, rotatable by a spindle 67 through gears 69, 70. The spindle 67. which is driven by worm gearing from a spindle 10 of the motor, is carried by a spring-controlled pivoted bracket 68, engaged by a lever 72". By moving this lever, the wheels 69, 70 can be moved out of gear, so that the pad 74 may remain in any position to which it is set by means of a hand-operated worm-spindle 76. Turntables.-The turntable. 15 may be provided, with a detachable covering 77 of silk, rubber, &c., Fig. 8 (Cancelled) which may be reinforced by a disc 78 of cardboard &c., and may be attached to the turntable by split pins 79 or the like. To facilitate removing a record from the turntable, a flat ring 42 placed on the centre of the turntable has studs 43 projecting through holes therein. Beneath these studs is disposed the curved end of a lever 44, Fig. 7 (Cancelled), so mounted in the casing of the machine that by turning the lever by means of an external knob 45 the ring 42 may be tilted, raising part of the rim of the record from the turntable. Cases.-The mouth of the internal horn 47 connects with an opening in the casing, which is provided with a sliding or hinged cover 55. A carrying-handle 61, collapsable. within a recess in the casing, is provided. When the machine is to be mounted in a cabinet a flanged ring 62 may be connected to the casing, in place of the cover 31, for securing the machine, to the top board of the cabinet. Tone-arms; tone-arm joints.-The sound-conduit comprises a curved tube 48, Fig. 3, (Cancelled) detachably fitted into the small end of the horn, and connected by ball bearings &c. 49 to the tone-arm 50. This is formed in two parts connected by a swivel joint 53. When not in use, the tone-arm and tube. 48 may be disconnected from the horn and stored within it. Attachements for storing needles.-A drawer 63, Fig- 2, (Cancelled) having compartments for needles, is located in the side of the casing, preferably in such a position that the sound-box may be swung over it to allow used needles to drop into it from the needle-holder.